Organ term

Taxonomic Applicability

Life Stages

Sex Applicability

How This Key Event Works

Serotonin stimulates locomotion and accelerates crawling in gastropods by pedal wave (step) elongation. Results by Pavlova 2001 indicate that dopamine controls snail speed by regulating sole length (amplitude of contraction of the muscle cells involved in pedal waves) and negatively impacts speed; serotonin positively regulates speed and determines the basic step length. For other mollusks that also use pedal waves (muscular waves), the mechanism of regulation by the neurotransmitters serotonin and dopamine are likely conserved.
Mackey and Carew (1983) found the primary target of 5-HT (serotonin)-controlled movement in aplysia (sea snail) was the pedal and pleural ganglia.
In the sea snail, Satterlie and Norekian (1996) identified a symmetrical cluster of pedal serotonergic neurons serves involved in wing spread and cerebral cells which control the activation of the pedal serotonergic neurons.

How It Is Measured or Detected

In gastropods, muscular wave action and locomotion may be monitored by video or (or photographs)of the snail crawling up a vertical, transparent wall. Waves and interwaves are visible as alternating dark and light transverse bands (Pavlova, 2011.